Flexible forms for building construction



Sept. 16, 1969 P. GRAHAM 3,467,354

FLEXIBLE FORMS FOR BUILDING CONSTRUCTION Filed April 5, 1966 2 Sheets-Sheet l.

9\ .l 9 "f1-3 mam 4 66% E F24 E i 9 Phi/lip Graham A ORNEIY Sept. 16, 1969 P, GRAHAM 3,467,354

FLEXIBLE FORMS FOR BUILDING CONSTRUCTION Filed April 5, 1966 2 Sheets-Sheet 2 FIG.7

mveNToR. Phillip Graham ATTORNEY wmf@ United States Patent O 3,467,354 FLEXIBLE FORMS FR BUILDING CONSTRUCTION Phillip Graham, 2825 Glenmore Ave., Pittsburgh, Pa. 15216 Continuation-impart of application Ser. No. 457,020, May 19, 1965, which is a continuation-impart of application Ser. No. 418,494, Dec. 15, 1964. This application Apr. 5, 1966, Ser. No. 540,314

Int. Cl. E04g 1]/04 US. Cl. 249-13 10 Claims ABSTRACT OF THE DISCLGSURE This disclosure pertains to a low cost, foolproof forming means for economically forming two-way curved or dished, reinforced thin shell concrete panels for small arched spanned buildings having corrugated shells. The forming means includes a durable elastic flexible edge form portion that coacts with metallic form parts to selectively dene the length, Width and thickness of a panel to be cast. The metallic parts position reinforcing and fasteners that allow like panels to be joined easily at erection. The form means includes means to inflate the elastic edge form to allow it to tightly confine the concrete and to allow it to be stripped easily. The form means also includes means to make lower cost multiple curved rigid form portions for molding the major surfaces of the curved building panels. The rigid form portions are made of reinforced concrete having an elastic edge form, perimetrical strand means with spaced fasteners and common wire fabric having its wires positioned diagonally with respect to the sides of the panel, the fabric being easily stretched and fastened to the perimetrical strand means, so it conforms to the multiple curvature required for the building panel to be cast. The rigid form portions may be used as building panels after they have outlived their usefulness as form portions, thus greatly reducing the form costs, thereby eliminating the worst obstacle to the use of thin shell construction for small buildings. In general the present invention describes numerous improvements to lower the cost of thin shell construction for small buildings, over the means described in my Patent No. 3,245,647 and my earlier related patents.

This invention relates to improvements in building construction including cernentitious type and plastic panels which can be readily interlocked or bonded together to obtain an integral building shell or the like, and relates also to the method and apparatus for casting such panels. This invention is a continuation-impart of my co-pending application Ser. No. 457,020, filed May 19, 1965, entitled Flexible Panel Form for Thin Shells, now Patent No. 3,245,647. Applicant also claims rights to an earlier filing date to common subject matter that is described in the present application, which was also described in his applications: Ser. No. 418,494, filed Dec. 15, 1964, now Patent No. 3,224,726, entitled Flexible Panel Form for Thin Shells; Ser. No. 86,814, filed Feb. 2, 1961, now Patent No. 3,161,938, entitled Flexible Panel Form for Thin Shells, and Ser. No. 785,273, filed Ian. 6, 1959, now Patent No. 2,971,237, entitled Flexible Building Panel Form. The application Ser. No. 457,020, is a continuation-in-part of application Ser. No. 418,494; application Ser. No. 418,494, is a continuation-in-part of application Ser. No. 86,814. The application Ser. No. 86,814 is a continuationin-part of application Ser. No. 785,273.

This invention particularly refers to a low cost ref. ICC' inforced thin shell panel having improved reinforcing and to a highly elllcient and nearly foolproof, adjustable forming means that has durable elastic flexible edge forms that allow quick and accurate molding of various shapes and sizes of curved and flat, precast, reinforced thin shell concrete panels.

My Patents 3,224,726 and 3,245,647 described simplified form means. My Patent No. 3,154,888, entitled Building Construction, and my Patent No. 2,971,237, describe how panels formed with such flexible forms can be used to build shelters; in addition, these patents list my numerous related patents that supplement the flexible form means in `building shelters.

The form means allows precast building panels to be molded accurately at low cost. The form means allows accurate positioning of fastening means along the edges of the building panels so the panels can be quickly and securely joined at erection. This fastening means allows precast panels to be erected dry with pins during inclement weather-grout mortar being inserted in the joints at a later suitable period. Non-elastic panel portions of the form means can be made of concrete; they can be used to mold the faces of the precast building panels, such concrete panel portions of the forms may be used as building panels after they have outlived their usefulness as form portions.

The building panel means has improvements over the combinations described in my earlier applications and patents, since it includes a rectangular panel having twoway curvature, perimetrical reinforcing strand means, which includes spaced connectors, and rectangular grid wire reinforcing that is positioned diagonally with respect to the panel edges. The panel may also have longitudinal reinforcing near its sides and along its center portion. Since the improved building panel acts almost wholly in compression when it is used to construct small arched buildings, it would be an ideal combination, since it would have adequate strength, While it would require far less labor to manufacturealso it would require mostly common wire fabric and other common reinforcing that would not have to be sent to a wire fabricating shop to have connectors fastened thereon.

The form means, including the concrete form portions that mold the faces of building panels, are an improvement over the form means described in my co-pending application Ser. No. 457,020, since it has a prefabricated perimetrical reinforcing strand means that includes spaced clevis and eye connector means thereon, along with common prefabricated wire fabric that is attached to the perimetrical strand means, the wire fabric having its strands positioned diagonally with respect to the sides of a rectangular panel, so as to allow common fabric to be easily curved to suit a panel that is curved in width and length. The form means has means to inflate the elastic portion of the form with air, Water or the like, so it can seal contacting edges so fresh concrete cannot leak from the confines of the form means.

An object of my invention is to provide a rectangular thin shell reinforced cementitious building panel, particularly a two-way curved panel, having a perimetrical reinforcing strand which includes spaced connectors, and having rectangular grid Wire fabric reinforcing that is positioned diagonally with respect to the panel edges.

Another object of my invention is to provide a flexible form including an inflatable, cuivable, flexible rubber-like plastic edge form strip that is able to accurately mold the edges of curved and straight, reinforced thin shell precast cementitious panels of various suitable widths, lengths and thicknessesfurthermore, to provide means to position connectors on the precast panel, so that like panels can be easily and securely joined at erection.

Other objects of my invention will become more apparent from the following description taken with the accompanying drawings wherein:

FIG. 1 is a plan view showing forms being used to mold a thin two-way curved reinforced concrete panel;

FIG. 2 is a sectional view takenA along line 2-2 of FIG. 1;

FIG. 3 is a sectional view taken along line 3-3 of FIG. 1;

FIG. 4 is an enlarged, fragmentary elevational view taken along line 4-4 of FIG. 1; 1

FIG. 5 is an enlarged plan view showing details of reinforcing and clevis connector means;

FIG. 6 is an elevational view taken along line 6-6 of FIG. 5;

FIG. 7 is an enlarged, fragmentary, sectional view taken along lines 7 7 of FIGS. 1 and 4; g

FIG. 8 is an enlarged plan view showing details of reinforcing at a corner;

FIG. 9 is an enlarged fragmentary sectional view taken through a typical side joint of a thin shell structure;

FIG. l is a view similar to FIG. 9, but showing a clevis with its leaves spread to allow easier positioning of panels at erection;

FIG. 11 is a view similar to FIG. 10, but showing a modification having a link to connect like panels;

FIG. 12 is a yfragmentary plan View showing details of a modified reinforcing means;

FIG. 13 is a perspective view showing a panel having a plurality of corrugations.

Referring to the drawings, FIGS. l-4 and 7 show how form assemblies F1, F2 and F3 are stacked in an arrangement for molding a precast, reinforced concrete building panel section 1. Additional assemblies may be stacked above the assembly F3. My Patents Nos. 3,161,938 and 2,971,237 describe such assemblies and their use in detail. The assemblies F1 and F3 are identical, as they each have a cured reinforced concrete form panel portion 2. Template bars 3a and 3b may be fastened together to form a template frame under the assembly F1, to help maintain the trueness of the assembly F1. Each of the assemblies has four exible adjustable elastic and resilient plastic or rubber edge form strips or gaskets 4, that form the perimeter of the assembly. One continuous strip may be used instead of the four pieces shown.

A building panel is cast within the assembly F2. After a panel 1 has cured, within the confines of the assembly F2, it may be removed from its form means so it can be used as a building panel or it may be used as a form portion, like the -form portions 2 of the assemblies F1 and F3, until it deteriorates from usage or is no longer needed .as a form. The concrete form portion 2 of the assembly F1 is used to mold the lower face of the panel, the whole assembly F1 holds the assembly F2 and the like in a true position to allow an accurate panel 1 to be cast. The stacked casting means allows the molding of duplications of intricately multiple curved building panels. Assemblies F1 and the like may be assembled at a casting plant-and have their concrete form portions 2 cast within their confines, then after the form portions 2 have cured, the assemblies including their portions 2 may be shipped to other casting yards to be used there as seed-like means to rnold additional form portions 2 and building panels 1.A

There are accurate modular spacing means for spacing stiff connector clevises and connector eyelets or eyes 6, about the edging of the form portions 2 and the panel 1. The connectors 5 and 6 provide a clevis-like pin connected interlocking means for joining building panelsto each other at erection. The connectors 5 and 6 are attached to perimetrical reinforcing wirestrands 7 and 8; Strands 7 are positioned transversely of an assembly and strands 8 are positioned longitudinally of an assembly. Strands 7 may have the connectors attached to them spaced with one type of modular spacing, while strands 8 may have the l is fastened to the strands 7 and 8. The fabric 9 for the panel 1 may be stretched over the form portion 2 of the assembly F1 to shape it, or it may be pre-formed over a similar form in a fabricating shop. Two intermediate longitudinal reinforcing wire strands 10` are fastened to the strands 7, as shown in FIG. 5. The strands 7, 8, 10 and the strands of the fabric 9 may be `welded rather than be merely twisted to each other, and they may be both twisted and welded. The connectors 5 and 6 or the like may be welded to the wires 7 and 8 in addition to otherwise engaging them. Wires 10 restrain the panel 1 and the form portion 2 from yielding outwardly in length.

Support-fasteners 11 are spaced about the assemblies to accurately space the apertures of the connectors 5 and 6. Support-fasteners 11 are fastened to each other and to the template bars 3a and 3b, with bolts 12 and dowel-bolts 13. Each support-fastener 11 includes a pin portion 11a. The connectors 5 and 6 are anchored to the pin portions 11a. Chairs 14 restrain the reinforcing means from bending downwardly out of alignment. The chairs 14 may be omitted when the fabric 9 is stiff and accurately bent. My Patent No. 2,897,668 describes suitable chairs.

The form 4 is described fully in my Patents Nos. 2,971,237 and 3,161,938. An edge form 4 has: spaced holes 4g; transverse slits 4f; longitudinal holes 4c, 4d, and 4e; a protruding medial portion or key groove mold offset 4a; and a restrainer offset 4b.

Pliable spacer strands M1 and M2 may be positioned along the full length of the form strip 4. The strands M1 and M2 are formed of spacer wires 15 that are welded to splice bars 17. Each bar 17 has a slotted hole. The slotted holes are accurately spaced to match spacing of holes 4g in the form 4. Supportfasteners 11 are described fully in my Patent No. 3,224,726. Each support-fastener 11 includes a pair of lowered crimped portions 11b and a pair of upper crimped portions 11c, to vary the height of the reinforcing strands 6 and the 'height of the supportfastener.

The same modular spacing is used to space: the support-fasteners 11, alongside of the strands 8, the connectors S and 6 on the strands 8, the holes 4g in the elastic strips 4 that are parallel to the strands 8 and the slotted holes in the splice bars 17 of the spacer strands M2. The same or a different modular spacing may be used to space the like parts alongside of the strands 7. The clevises 5 are spaced along the edging of an end and the edging of a side of the panel 1 and a form portion 2. The eyes 6 are spaced along the other end and the other side of the panel 1.

A restrainer or holder 18 may be used with each connector, along with the spacer strands M1 and M2, so as to restrain the connectors from being accidentally or wantonly pressured and uncoupled, or from being moved out of their true position. The restrainers 18 yield to allow a crane to lift a cured panel 1 from the contines of an assembly F2 and the like that encircles it. A restrainer is described in detail in my co-pending application Ser. No. 457,020.

Each edge form 4 may have valves 19 inserted and fastened to it, like valves are attached to bicycle tires. 'Ihe valves 19 allow air, water and the like to be inserted in the forms 4 to stiften them, particularly when the forms are stretched as shown in FIG. 7. The holes 4d would be pressured to a higher degree than would the holes 4c. The ends of the holes 4c and 4d may be sealed with resilient plugs 26 that are cemented to the strip 4.

Since an eye 6 is thinner than a clevis 5, an adapter, like the adapter shown in my Patent No. 3,161,938, is slid onto the eye to thicken it so it can be aligned properly.

The fluid concrete may be inserted through the access holes 2a in the form portion 2 of assembly F3 or the concrete may be deposited onto the panel 1 of the assembly 5 F1 before the assembly F2 is capped with the assembly F3.

As shown in FIG. 9, a pin Z is inserted through the connectors 5 and `6 to pin the like panel 1b and 1c together. Grout 21 is inserted into the joint to further key the panels together. The pin 20 may be split like a cornmon cotter pin is split.

The connectors 5 and 6 are shown as being made of stampings that are bent so that they may be looped about the wires 7 and 8. The connectors 5 and 6 may be welded to the wires 7 and 8 to hold them in true positions. The connectors as shown may be locked to make them strongly secure and to allow them to be fastened to the wires 7 and 8 without welding. The connectors 5 and I6 have fingers 5a and 6a that are bent over the adjacent connector portions to lock the portions together. The connector leaves may be spot welded together near the fingers 5a and 6a, or the fingers may be omitted and the leaves 5b and 5c or the like may be locked together by welding spots only.

The connectors 5 and 6 are bent up to connect to the wires 7 and 8 when the Wires 7 and 8 are positioned higher than the apertures of the connectors. The connectors have slotted holes, such as the slot Sd in the clevis S. The slot 5d engages the pin portion 11a and the restrainer 18. The connectors have long slotted holes such as the slot 5f in the clevis 5. The slot 5f allows the wire 10 to be fastened to the wire 7 at the center of the clevis 5, as shown in FIG. 5. The long slots also allow the wires 7 and 8 to be coupled to the connectors at a corner, as shown in FIG. 8.

Fiber glass reinforcing including grid reinforcing may be used when the building panels are to be subject to excessive moisture. Such a grid reinforcing fabric may have each grid strand made up of numerous glass fibers that are bound together with plastic or the like as described in Patent No. 2,921,463.

The apertures of eyelets 6 must be aligned with the apertures of the clevises 5 during erection of the panels, which requires considerable skillful manipulations of the panels. The leaves 5b and 5c of each clevis 5 may be spread to a buttery shape after a panel has cured, as shown in FIG. 10, to allow the connectors 5 .and `6 to be brought into alignment more readily. After such alignment, a tool pin 22 may be inserted in the crotch, then the leaves may be pressed with a tool to position them as shown in FIG. 9. A phantom outline 20a indicates a pin position.

When the casting operations are crude and the accuracy of the positioning of the connectors S and 6 is not close enough to align the connectors as shown in FIGS. 9 and 10, the assemblies may be modified so the panels 1d and 1f are slightly narrower than the standard width so the clevises 5 and eyelets 6 do not engage, as shown in FIG. 1l. A pin link 23, which may be resilient, is sprung and held with a tool, while it is coupled to the connectors 5 and 6. After the coupling is secured, the tool is removed and tension causes the clevises 5 and eyelets l6 to be securely and tightly joined. The panels may be kept a standard width, while the connectors 5 and 6 are positioned back slightly towards the concrete so the connectors do not overlap when they are erected. The means shown in FIG. l1 may be used to make and erect a panel between two other panels that have already been erected. All of the connectors around a building panel may be eyes 5, when the link means 23 is used generally.

The modification shown in FIG. 12 has a wire eye connector 24 wrapped around or twisted onto the strand 8. Wire clevis connectors (not shown) that are fastened like the connector 23 is fastened may also be used. Wire clevises are shown in my Patent No. 2,971,237. The Wire connectors may be welded to make them stronger. Modified wire connectors may be welded without the wrappings. The wire connectors would not be as useful as the connectors 5 and 6, but they may be used to advantage where wire is lower in cost than the connectors 5 and 6.

Wire connectors may be made with square wire so a pin can bear better against them.

When facilities are available to cast, cure, ship and erect large panels economically, a multi-corrugated precast panel 25, such as the panel shown in FIG. 13, may be made in casting yard with form assemblies being used to cast a portion of the panel, then to enlarge it by molding additional corrugated portions to it. A panel portion or corrugation 25a may be cast, then a portion 25C, and finally a portion 25b may be cast to form a complete panel 25.

While I have illustrated and described several embodiments of my invention, it will be understood that these are by way of illustration only, and that various changes and modifications may be made within the contemplation of my invention and within the scope of the following claims.

I claim:

1. A form for molding at least a portion of a thin cementitious building panel having stiff embeddable strand means spaced along at least the edging of said building panel portion, said form comprising elongated elastic strip means, a base means for supporting said strip means, said strip means has at least one longitudinal hole means extending substantially throughout its length, said strip means including sealing means to allow said hole means to remain air-tight, a valve means fastened to said strip means and engaged to said hole means to allow said strip means to be iniiated, said strip means having an effective height substantially equal to the thickness of said building panel portion to be cast, said strip means having a length at least sufficient to mold said edging of said building panel portion, said strip means being sufficiently flexible so as to be bendable in all directions to allow it to follow the contours of curved and flat planes, said strip means adapted to confine the fresh cementitious aggregate of said building panel portion deposited onto said base means and defining the shape of said edging, said strip means having spaced transverse holes through an intermediate portion of its height and substantially parallel to the plane of said base means, said transverse holes adapted to receive extending end portions of said embeddable strand means, a plurality of fastener means disposed along the length of said strip means for fastening said strip means to said base means and adapted for anchoring the said end portions of said embeddable strand means, said end portions including connector means, each of said connector means including aperture means, said fastener means including integral fastener pin means adapted for coupling said connector means wherein said anchoring is provided with each of said pin means having a longitudinal axis, all of said pin means being positioned so their said longitudinal axes are parallel t0 each other, said fastener pin means adapted to accurately position said connector means so that said aperture means face towards the planes of major surfaces of said building panel portion, each of said fastener pin means including an integral end portion projecting outwardly away from said base means, whereby said elastic strip means is stiffened and enlarged by infiating it and whereby said elastic strip means is deflated to allow it and said building portion to be removed together from the confines of said spaced fastener means without disturbing said fastener pm means.

2. A form as recited in claim 1, together with a plurality of restrainers disposed along the said length of said strip means each of said restrainers being positioned adjacent to one of said transverse holes, each of said restrainers including a restrainer pin portion that penetrates into one of said aperture means, each of said restrainers including an extending portion that extends outwardly from said restrainer pin portion, whereby said strip means and said building panel portion are held together when they are removed from the confines of said spaced fastener means without disturbing said fastener pin means, so as to allow said strip means to protect said building panel portion during shipping and storage operations.

3. A form as recited in claim 1, wherein each of said extending portions includes a hooked portion, each of said fastener means including a grippable portion to which one of said hooked portions is engageable so as to restrain each of said connector means from uncoupling from said fastener pin means when said embeddable strand means are pressured by minor forces that are parallel to said fastener pin means, each of said hooked portions having yieldable means to allow it to become automatically uncoupled from said fastener means when a great force is used to remove said building panel portion from said contines of said fastener means.

4. A form as recited in claim 1, wherein said strip has transverse slits extending from said spaced transverse holes to an edge of said strip means to allow said strip means to be positioned after said anchoring of said end portions.

5. A form for molding at least a portion of a thin twoway curved cementitious building panel of substantially rectangular outline, said building panel portion having stiff connector means spaced along at least the edging of said building panel portion, said form comprising an elongated elastic strip means, a base means for supporting said strip means, said strip means having an effective height substantially equal to the thickness of said building panel portion to be cast, said strip means having a length at least suicient to mold said edging of said building panel portion, said strip means being sufficiently flexible so as to be bendable in all directions, said strip means adapted to contine the fresh cementitious aggregate of said building panel portion deposited onto said base means and defining the shape of said edging, said strip means having spaced transverse holes through an intermediate portion of its height, said transverse holes adapted to receive extending end portions of said connector means, a plurality of fastener means disposed along the length of said strip means for fastening said strip means to said base means and adapted for anchoring the said end portions of said connector means, each of said connector means including aperture means, said fastener means including integral fastener pin means adapted for coupling said connector means wherein said anchoring is provided, each of said pin means having a longitudinal axis, all of said pin means being positioned so their said longitudinal axes are parallel to each other, said fastener pin means adapted to accurately position said connector means so that said aperture means face towards the planes of major surfaces of said building panel portion, each of said fastener pin means including an end portion projecting outwardly away from said base means, said base means comprising a lower elongated elastic strip means positioned below said strip means, said lower strip means having lower spaced transverse holes through an intermediate portion of its height, said lower strip means having an effective height substantially equal to that of said strip, said base means having a cementitious form portion, said cementitious form portion filling the space confined by said lower strip and being of equal thickness to said height of said lower strip means, said cementitious form portion having a two-way curved shape that defines one of said major faces of said building panel portion, perimetrical reinforcing strand means positioned adjacent to said lower strip means and largely embedded within said cementitious form portion, said perimetrical strand means includes spaced lower connector means that extend outwardly through said lower transverse holes, a i

diagonally across said cementitious form portion and engaging said perimetrical strand means, a plurality of lower fastening means disposed below and fastened to said fastener means, each of said lower connector means including aperture means, each of said lower` fastening means including integral lower pin means for coupling said lower connector means, said lower pin means being parallel to said pin means, whereby said curved building panel can be cast readily.

6. A form as recited in claim 5 together with a cap means, said cap means comprising an upper elongated elastic strip means positioned above said strip means, said upper strip means having upper spaced transverse holes through an intermediate portion of its height, said upper strip means having an effective height substantially equal to that of said strip, said cap means having an upper cementitious form portion, said upper cementitious form portion filling the space confined by said upper strip means and being of equal thickness to said height of said upper strip means, said upper cementitious form portion having a two-way curved shape that defines the other of said major faces of said building panel portion, upper perimetrical reinforcing strand means positioned adjacent to said upper strip means and largely embedded within said upper cementitious form portion, said upper perimetrical strand means includes spaced upper connector means that extend outwardly through said upper strip means, a plurality of upper reinforcing grid strands arranged in grid formation and extending through a medial plane of said upper cementitious form portion, said upper grid strands being positioned diagonally across said upper cementitious form position and engaging said upper perimetrical strand means, a plurality of upper fastening means disposed above and fastened to said fastener means, each of said upper connector means including aperture means, each of said upper fastening means including integral upper pin means for coupling said upper connector means, said upper pin means being parallel to said pin means, whereby said curved building panel can be wholly cast accurately.

7. A form as recited in claim 5 together with intermediate longitudinal reinforcing strand means positioned substantially centrally of the width of said cementitious form portion, whereby said cementitious form portion is restrained from bending.

8. A form as recited in claim 5, wherein each of said grid strands comprises a plurality of fiberglass strands, whereby said grid strands can resist corrosive elements.

9. A form as recited in claim 5, together with random length strands of fiber glass reinforcing embedded in said cementitious form portion, whereby said cementitious form portion is restrained from bending and deteriorating.A

10. A form as recited in claim 5, wherein each of said lower'connector means comprises a sheet metal stamping.

References Cited UNITED STATES PATENTS 2,579,423 12/ 1951 Ford 249-33 X 2,971,237 2/ 1961 Graham 249-33 3,245,647 4/1966y Graham 249-13 J. SPENCER OVERHOLSER, Primary Examiner ROBERT D. BALDWIN, Assistant Examiner 

